New to baking and already desperate for help!

Hello! I am brand new to baking, as well as to this site! We got a Nutrimill for Christmas, and I have already put it to work learning how to make wheat bread with fresh ground wheat. My mother makes wheat bread that is as light as white bread and very delicious. I am trying very hard to learn her recipe, but failing miserably! It has no spring once it gets into the oven, making the loaves very heavy and doughy on the inside. It cooks on the outside long before the inside can cook all the way. This is the fourth time we've made this particular recipe with the very same failure--my husband thinks we should switch to another recipe, but I know this one can work! Here it is:5 C very warm water, divided2 T yeast1/2 C honey or brown sugar3/4 C oil2 T salt2 C white flour8-10 C hard white wheat flour1/2 C flax seed (optional)3 T gluten2 T dough enhancer

Mix 3 C warm water with yeast and honey or brown sugar. Let yeast dissolve. Add the remaining ingredients and knead 8 min. total. Divide into loaf pans and rise until almost double. Bake at 325-350 degrees. Makes 3 large loaves and 1 small loaf.It always seems to go wrong once we stick it in the oven. It rises to almost double, when we put it in the oven at 325 degrees. After that, it rises very little--maybe another fourth of an inch, when it ought to be rising at least two inches (approximately). The past three times we have been making it in a convection oven, but the fourth time we tried the conventional oven--with the same results. Our yeast is good, our dough enhancer and gluten are fresh, and we've been careful not to add too much flour. I just don't know what I'm doing wrong!!! Please contribute any ideas!